/**
*
* @param type $article_id
* @param array $datas
* @return Article
*/
function update($article_id, Article $article)
{
$article->updated_at = new \MongoDate();
$article->update_count++;
unset($article['_id']);
$this->_collection->update(array('_id' => new MongoId($article_id)), $article->toArray(), array('safe' => true));
return $article;
}
